South-west England Chalk Group Lithostratigraphy: Jukes-Browne & Hill, 1903, 1904 - Cenomanian Limestone Bed C
This is a relatively softer (compared to A or B), sandy, glauconitic chalk, with common phosphatic nodules and derived, phosphatised fossils (Jukes-Browne & Hill, 1903). The brachiopod Orbirhynchia wiesti is a characteristic indigenous fossil, and the belemnite Praeactinocamax plenus also locally occurs (Jukes-Browne & Hill, 1903).
Macrofossil biozonation: Modern biostratigraphical studies indicate assignment of the derived fauna to the A. jukesbrownei Zone and C. guerangeri Zone, while the indigenous fauna represents the M. geslinianum Zone (Wright & Kennedy, 1981,1984).
Correlation: see Correlation with other lithostratigraphical schemes for south-west England
see Correlation with other UK regions
JUKES-BROWNE, A J & HILL, W.1903. The Cretaceous rocks of Britain. Vol. 2 - The Lower and Middle Chalk of England. Memoir of the Geological Survey of the United Kingdom.
WRIGHT, C W & KENNEDY, W J. 1981. The Ammonoidea of the Plenus Marls and the Middle Chalk. Monograph of the Palaeontographical Society, London: 148 pp., 32 pls (Publ. No. 560, part of Vol. 134 for 1980).
WRIGHT, C W & KENNEDY, W J. 1984. The Ammonoidea of the Lower Chalk. Part I. Monograph of the Palaeontographical Society. London: 1-126, pls 1- 40 (Publ. No. 567, part of Vol. 137 for 1983).